If they succeed in their effor to push further to come more closer to the center of the people, then I think that is when they start to reap the fruits of their efforts and finally win the hearts and minds of the truly king mackers in the country to get to political power (the over 80% of the general population).
It will be no more the assumption that those who rule in Addis go out to rule also the rest of the country.
ODP can even have the potential to become the first major party in the country (like the 2 Volksparteien in Germany, Christial Democrats and Social Democrats, and Democrats und Republicans in USA, for example).
Those who were granted amnesty to come back home and engage themselves in a peaceful and democratic political discourse used (not to say spoiled) the chance to come home and stay what they used to be all along for decades: the paper tigers. One thing is also true of this latter group: they are unable to learn.